"I've had depression, like clinical depression, for my entire adolescence," de Blasio says in the video. "It made it easier, the more I drank and did drugs, to share some common ground with people that I wouldn't have. It didn't start out as a huge thing for me but then it became a really huge thing for me."

In the video, de Blasio speaks about drinking and smoking marijuana when she was in college, as well as the outpatient treatment that started her on the road to recovery.

De Blasio's father sailed to a landslide victory last month over Republican candidate Joe Lhota to become New York's first Democratic mayor in more than 20 years. One key to his victory was a connection with voters, formed in part via his mixed-race family, particularly his son, Dante, and wife, Chirlane McCray, who played a prominent role on the campaign trail.

Chiara's story has until now stayed out of the public eye.

"As parents, our instinct has been to protect our daughter and privately help her through a deeply personal struggle," her parents said in an e-mail to supporters that linked to the video. "But not only has Chiara committed to her own health, she is also committed to helping young people everywhere who face similar challenges."

According to the video, Chiara de Blasio has completed treatment and is now trying to reach out to others.

"It's just important for people to realize, anybody who is watching this, that if you're suffering and if you're depressed, you're dealing with mental illness, and you think that it might have something to do with your drug abuse or drinking, or if you're just suffering from both of those at the same time and you think that they're completely unrelated to one another," she says, "getting sober is always a positive thing."

De Blasio makes minimal reference to her parents, not naming either and mentioning only that both were "very emotionally committed to try to figure out some way to get me better."

Participating in her father's campaign after completing treatment "was like the greatest thing ever," de Blasio says, although she doesn't specify that it was the mayoral race.

White House Drug Policy Director Gil Kerlikowske issued a statement Tuesday afternoon praising the young de Blasio for speaking out.

"Chiara is giving a voice to the millions who suffer from substance use and mental health disorders, and we encourage others to join her," he said.

"By talking about addiction in the light of day -- and by celebrating recovery out loud -- we can help correct the misinformation and stigma that too often become obstacles for the millions of Americans who deserve to live healthy, productive lives," Kerlikowske said.

De Blasio decided to speak out "because people are suffering from this disease and dying from this disease every day. And we really can't do anything as a society to help those people until we start talking about it," she says. "And nobody can do sobriety on their own."